John mcneillj



` TaaZZwhomz'/f maf/concern.' i i zBe it known ,that I, n, `the city,county, and "State of New York, i haveinvented anewfandusefulImprovement in Charcoal-Furnaces for Reburning the Animal Charcoal usedinSugar-Ren i f "ing ,z and'I do hereby declare that the follow- 1 ingis a full, clear, and exact description of the same, reference` being`had to the accom- `panying drawing, formingxpart of this specification,`in which` n Figure l, is a transverse verticaljsection of a furnaceconstructedfaccording to my inn `vention.

section of the same in the line w,, of Fig.` l. iFig. 3, isa sideVviewon a larger scale, of n n foneof the hollowbeams which support the"tubes. "samef i i.

' `Similar lettersofreference indicate corresponding `parts 'in theseveral figures.

` f `In carrying out `my invention `departfrom the generalconstructionof the furnace and `arrangement of the tubes therein, `but myinventionconsists chiefly in sup @porting the tubesfnear the middle of theirlengthby hollow or `tubularbeams one end ofieach of which entersthechimney or escmmcoAL-rUnNA-cn.

` i `specifies@ion of `rafters `1 atent No. 12,602, dated March 27,1855.

JOHN MGNEILL, of

Fig. 2, is a longitudinal vertical Fig. 4, is a transversesection `ofthe The object of this invention is to `prevent the sagging and speedydestruction of the `retorttubes which injthe furnacesnow in n `Ruse forre-burning animal charcoal in sugar frefineries, is consequent `upon theintense `"heattowhich they are exposed.

I do not cape `flue and the other end is `open to receivecold air fromthe exterior of the furnace.` IThe draft `of the chimney causes co-n-`stantcurrents of cold air topass through the beams;` and thuspreventtheir being i burned out and` failing to`" give `an` eiiicient supporttothe retort tubes.

` A is the fire chamber, in the center of the furnace,` and" B, B, theretort tubes `ar-V rangedin two rows on` opposite sidesof the `grateinclining toward each other at the top i in the usual way.

n C, is the fluewhichfis in immediate comi .i munication with thechimney, communicat- `1 ing withthe fire chamber of ythe furnace by ntheopenings D, fluesE, and `openings F. G, G, are the :tubular beams,which supn port the retort tubes `about midway between thetop and:bottoml n These beams are of castiron`. `They.maygbefsoluare'externally i and cylindrical internally as shown, or of u otherformexternally and internally. `They ,run longitudinallyfrom*end to `endof the furnace and `are built into the front end thereof, and into thewall separating the rear end thereof from the flue C, and are open atthe ends to admit currents of cold air through them from outsidethefront of the furnace into the flue C, as indicated by arrows in Fig.2, which currents will always be `induced by the draft of the chimneywhen re is started in the furnace. These currents of cold air `will"prevent the rapid burning of the beams which without vthem would ensue,and by keeping the beams comparatively cool will enable them to serve asa stiff and durable support to the tubes.

In order to avoid making the beams too long and'also` to `provide betterfor eXpansion and contraction I make each in two lengths united byflanges and a bolt or bolts or in any suitable manner whereby eXpansionis provided for and support them by an arched wall H, of masonryreaching across the furnace at about the `middle of its' length. Thiswall also serves to support and strengthen the side walls of the furnaceand support the roof or top plates.`

Having thus fully described my invention I will proceed to state what Iclaim and desire to secure by Letters Patent.

I do not claim a `hollow or tubular iron beam, merely as such, as I amaware thatI hollow beams have been and are commonly used in variousstructures. But

1. I claim supporting the retort tubes B, B, by a hollow or tubular beamor beams with open ends, applied substantially as herein described sothat one end of each is in communication with `the cold or atmosphericair outside the furnace and the other withthe chimney or escapeflue,iwhereby `a current vof cold air is caused to be induced ney `orflue, for the purpose of keeping it comparatively cool, preventing Vitburning, and rendering it a firm and durable support to the retorttubes.

` 2. And I also claim constructing the furnace with one `or more archedwalls H, eX- tending across it substantially as described to support thejoints in the beams G, G,

'through the-beam by the draft of the chimwhen the said beams are madein two or n more lengths, and also to support the side walls and roof.

. JNO. MCNEILL.

i Witnesses: Y I l i Jos. GEO. MASON, J. W. CooMBs.

